Richest African Countries by Decade

Let's say you wanted to replicate this quiz. You would list the 10 richest African countries by per-capita GDP in 1960 the third column. Then, list the GDP per capita of all of those countries in the second column. Finally, list the year (1960) for all of those countries in the first column. Do the same but list the GDP per capitas of the 10 richest African countries for every decade 1970-2020. In the first column, list the corresponding year (the year all of those African nations had that GDP per capita). Finally, go to Step 4 -> Advanced -> Format as "Groups of Things", then choose create 4 blocks and set the Group Order as Best Fit. Press "Format Groups" and you should be good!